On Fri, 28 Feb 2014 22:55:11 +0100 Peter Zijlstra <pet...@infradead.org> wrote:
> On Fri, Feb 28, 2014 at 01:51:50PM -0800, Paul E. McKenney wrote: > > On Fri, Feb 28, 2014 at 10:27:00PM +0100, Peter Zijlstra wrote: > > > On Fri, Feb 28, 2014 at 01:17:33PM -0800, Paul E. McKenney wrote: > > > > This code isn't running in idle context is it? If so, RCU will happily > > > > free out from under it. CONFIG_PROVE_RCU should detect this sort of > > > > thing, > > > > though. > > > > > > Well, interrupts/NMIs can happen when idle, but the interrupt/NMI > > > entry code deals with the idle state AFAIK. > > > > Yep, rcu_irq_enter() and rcu_nmi_enter() deal with that. More worried > > about this being code invoked from some energy-efficiency driver or > > another within the idle loop. > > Right, so any tracepoint can end up there; but I thought there was > already the rule that tracepoints needed RCU enabled. There is and we have special tracepoint caller for those cases we want a tracepoint out of RCU scope. These will reactivate rcu in the tracepoint code. trace_<tp_name>_rcuidle(...) -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
